Tensile strength testing apparatus



A, l.. JBABCOCK TENSIILE` STRENGTH TESTING APPARATUS v Filed Apr'i 25, 1945 2 sheets-sheet 1 HunHnm May 27, 1947.

May 27,y 1947. A. 1 BABcocK I TENSILE STRENGTH TESTING APPARATUS Filed April 23, 1945 2 IsheesL-sheet 2 "3. l INVENToR. #mf/Pr L coc ATT IPA/ZY Patented May 27, L1947 ammi- .Albert L; Babcock; Newark, .If., assigner tojv .lieder al Telephone and. Radio .(fiornoration,

New York,.oN. Y.; `a. corporation of Delaware V aiisiieatmsnias, 1941s, sedative. teugels' claims. (Gifte-,Jesi

.This invention relates to a tensile strength te's'ti ing apparatus and more particularly to anappa ratus for testing the quality of welding or solder-- ing of lead wires for small 'erevices such as dry rectifier elements.Y

Since it is essential that the welded` contacts of thev leads for el'ectrical'apparatus have a long` life of service', various deviceshavebeen provided` for testingi'such connections.

It is the object-of the present ihyentlonto .provide aVV simple and efficient welding strength test= ingapparatus which enables the testing 'of the welding connection for a certain predetermined strength'.A Y

It is a further objectof thepresent invention to actuate the testing -devfthe'r manually or preferably pedally. y ,Y

With these and other objects'i-n view theprese ent invention will become apparenty and clearly understood in connection with 'theaccompanying drawings, in which:

jFigu-res l and 2 are` plan vand elevational views ot the'apparatns and frame;

Fig.g3 is a plan view of -the Iapparatus on 'enlarged scale; y A o g '-Fig. i yis a partly sectional elevational' View of theapparatus; Y

Fig. 5 i-s a Vside ,viewwof the apparatus shown in operative lampedposition. and

Fig. 6 is a side view of the apparatus shown in inoperative position.

Referring now to the drawings the apparatus I, according to the present invention, is supported by a table-like frame 2 and fastened to the table 2 by screw bolts 3.

The apparatus I comprises a base 4, mounted on the top of the table 2, which base 4 carries two parallel arranged U-brackets 5. Two slides 61 and 62 glide along the U-brackets 5 and the movement of the two slides is limited between pairs of pins 1, 8 and 9 which are arranged opposite each other in each of the U-brackets 5. Slide B1 is allowed to move between the pins 'I and 8 and slide 62 between the pins 8 and 9.

The U-brackets 5 are secured to the base 4 by a number of screw bolts I0.

Each one of the slides 61 and 62 carries a pair of angle members' II and I 2, the angle members II being fastened to the slides 61 and 62 respectively, by means of screw bolts I3 so that they are movable with these slides. Whereas the angle member II has its branches arranged at an angle of 90, the angle member I2 has its branches at an angle of somewhat less than 90. Another screw bolt I4 carried by the upper branch of theah'gle member I I yand peneti'ating a hole I5 of the upper ybranch of the angle member I2 holds the angle member AI2 loose connecting position with the angle member II so that'theupper lbranches 'of the `angle members Il `and I2 provi-de an 'open space between them in theV inoperative position .of the apparatus. The upper branch of the angleAmember 'I1 Jmay "be 'equipped near its upper end/.with a small 'pin I5 and the upper branch of `the angle member I2 may b'e equipped. on the same level with a corresponding .hole I 7 Twhich isY adapted vto receive the pins iIi'.

. v-iEi'a-ch angle member LII is further equipped with a clamp "I8 whichis turnably connected 1oy-means of'aother screw bolt I9 or the like withthe upwards extending-branch of the 'angle member I I The :clam-p i3 is adapted to be turned over and to rclamp the two upwards extending branches of the ari-gie members II and vl2 and, therefore, the inner width of the clamp "t8 isslightly larger than the thickness of the "-two upper branches 'of the angle'members II and I2. Handles 28 are integrally formed they clamps I-8 morder to lift for'lower the clamps I 8 from or upon the angle members II and I2 without using Vgreat force.

The outer ends'of the slides 61 and "62 carry eye bolts 2|1 and 2I2. Pulley-sv 2:214 and i272,2 'are mounted on top of-the-tab-le oneach-side'iof the apparatus I-andfa string `cr chain 23, one end -of which is connected with the eye bolt 2I1, runs over the pulley 221 and then through a hole 24 in the table 2 over a pulley 25 and pulley 26 to a foot treadle 21 which is mounted on the base of the frame 2. The pulleys 25 and 26 are mounted on the underside of the top of the table 2. Another string or chain 28 is connected with the eye bolt 2|2 of the slide 62 and runs over the pulley 222 through another hole 29 in the top of the table. The end of the string or chain 28 carries a predetermined weight 30.

The apparatus according to the present invention works in such a way that the lead wires 3l of the rectifier element 32 are clamped between each group of angle members I I and I2 and then exposed to the stress of any predetermined weight. In order to stress the lead wires 3I it is rst necessary to move both slides to their most extreme positions, namely so far to the right that the slide 61 abuts the pins 8 and slide I52 abuts the pins 9. This arrangement is necessary with the assumption that the foot treadle 21 is connected with the left slide 61 of the apparatus, whereas the right slide 62 is connected through the eye bolt 2I2 with any predetermined weight 30. After the two slides 61 and 62 are brought to their proper positions, first one Wire 3| is inserted between the upper branches of the angle members and l2 of the slide 61. In order to provide an anchorage for the inserted wire the pin I6 is arranged on the angle member l When the wire is thus inserted, the clamp I8 mounted on slide 61 is turned :down by pushing the handle 26 thereby clamping'together the 'upper branches oi the angle members Il and |2 and at the same time pressing between them the lead Wire 3|. Essentially the same procedure is now done with the right hand lead Wire 3| which is then of at least two lead wires extending from an j E" i 2,421,002 1i.; 551';

vof 'saidf first 'clamping means in the 4opposite direction; L f

2. In an apparatus for testing connecting joints electrical element, a base, guides fastened to said clamped between the angle members and I2 mounted on the slide 62. After Allhavingnovv the# .rectier element clamped between the'two groups `of angle members and |2 through its lead wires j .3|, the treadle 21 is operated and thereby'the` l .slide 61 is moved to the left in the direction of the arrow 33. By this movement the right slide 62 will also be moved in thesame direction and the lead wires and their welded connections with the rectiiier element 32 form the only connecting means between the slides 61 and 62 exposed to the predetermined weight pulling on slide 62. It has been' found that for the purpose of these smalll rectifier. elements 32 a Weight of three pounds is suicient, since this isabout the maximum stress to which the welded connectionsare subjected. During the testing operation the slides 61 and @move toithe left sideuntil `they abut the pins 1 and 8, respectively." During this travel the welded connections ofthe lead Wires 3| working as the connecting means between slides 61 and 62 carry the Whole weight 30. VUpon releasing the foot vtreadle 21 the slides 61 -and 62 will return to their original positions. The clamps I8 can then be lifted againiby.l means of their handles 20 and the rectier element and its Wires 3| easily-removed and a newrectier element for the next test be inserted. f

While I have disclosed the"principles of my invention in connection :with one specic embodiment, it will be understood that this embodiment is given byway of example only and not as limiting the scope of the invention as set forth in theobjects andthe appended claims; What I claim is: Y 1. lIn an apparatus for testing the tensile strength of an element, oppositely positioned movement in A`said guides and for clamping the ends of said lead wires such that said wires with `said element serve as the connecting means between saidclamping means, means for limiting the movement of one of said clamping means in one direction, means for hunting the movement of both of said clamping means in the opposite direction, means for moving one of the said clamping means in the said one direction, and means exerting a predetermined constant force on the other clamping means immediately upon moving of said one clamping means in said opposite direction.

3.' In 'an apparatus as set forth in claim 2, said moving means comprising atreadle and a connecting means between one of said clamping means and said treadle, saidv force exerting means comprising a weight and a connecting means between the other of said clamping means and said weight.

ALBERT L. BABCOCK.

REFERENCES CITED The following references are'of record in the leof this patent:

u STATES PATENTS 1,749,297 Norman Mar. 4,1930 

